[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Parallel Printer Port is not working
I'm trying to drive LCD(HD44780) using included software "etrax100parlcd.c"
In spite of my enthusiastic effort, some bits of parallel port are impossible to control.
Short example is below.
Hyojun Kim(Research Engineer in Finalsolution)
#define LCD_E 0x00010000 // LCD enable
#define LCD_RW 0x00020000 // LCD read/write
#define LCD_RS 0x00040000 // LCD register select
#define PAR_OE 0x00100000 // Output Enable on par port
*R_GEN_CONFIG = 0x00d6a98c; // select parallel port, disable SCSI
*R_PAR0_CONFIG = 0x00000060; /* Manual-mode, enable port,
immeditate mode change */
*R_PAR0_CTRL_DATA = LCD_E; // (/INT) this bit is OK
*R_PAR0_CTRL_DATA = LCD_RW; // (/STROBE) This bit is always HIGH, uncontrollable
*R_PAR0_CTRL_DATA = LCD_RS; // (/AUTO_FEED) This bit is OK
*R_PAR0_CTRL_DATA = PAR_OE; // This bit is always LOW, uncontrollable
*R_PAR0_CTRL_DATA = 0x00080000; // (/SELECT_IN) This bit is always LOW, uncontrollable